NAVIGATION
Catalogs work like categories.
You can add your entries to a certain catalog (one or more) and later display entries collected in different catalogs on your website.
Here you can hide all entries added to a certain catalog just by set the catalog to inactive.
Makes the administration of catalog events easy and flexible.
Note: Deleting a catalog does NOT delete the entries within this catalog . It just deallocates the entry from the catalog!
When a catalog is selected within any CP and then it's deleted here, a warning appears in the overview, you should update the CP's in this case.
The Module can handle this issue in the frontend though.